Fine pattern structures having block co-polymer materials and methods of fabricating the same

ABSTRACT

A method for fine pattern structures includes forming a pattern formation layer over a first region and a second region of a substrate, forming a first block co-polymer layer in the first region, forming a second block co-polymer layer in the second region, etching the first and second block co-polymer layers, and forming the fine pattern structure in the pattern formation layer in the first region without forming a pattern in the pattern formation layer in the second region.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority under 35 U.S.C 119(a) to KoreanApplication No. 10-2013-0148248, filed on Dec. 2, 2013, in the KoreanIntellectual Property Office, which is incorporated herein by referencein its entirety.

BACKGROUND

Processes and materials for fabricating nano-sized structures areincreasingly in demand with the development of mechanical, electrical,chemical and biological devices (or systems) having nano-scalecomponents. Particularly, as the nano-scale components are scaled downto have a size of several tens of nanometers, need of the processes andmaterials for fabricating the nano-sized structures is rapidlyincreasing.

SUMMARY

Embodiments of the present disclosure relate to semiconductor devicesand methods of fabricating the same, and more particularly, to finepattern structures having block co-polymer materials and methods offabricating the same.

Various embodiments are directed to fine pattern structures having blockco-polymer materials and methods of fabricating the same.

According to some embodiments, a fine pattern structure includes a lowerhard mask layer disposed on a pattern formation layer having a firstregion and a second region, a plurality of first upper hard maskpatterns disposed on the lower hard mask layer in the first region toexpose portions of the lower hard mask layer, a second upper hard maskpattern covering an entire surface of the lower hard mask layer in thesecond region, guide patterns on respective ones of the first and secondupper hard mask patterns, a plurality of neutralization patterns onrespective ones of the exposed portions of the lower hard mask layer inthe first region, a first block co-polymer layer covering the guidepatterns in the first region and the plurality of neutralizationpatterns, and a second block co-polymer layer covering the guide patternin the second region.

According to further embodiments, a method of fabricating a fine patternstructure includes forming a pattern formation layer and a lower hardmask layer on a substrate having a first region and a second region. Afirst patterns including first upper hard mask pattern and a first guidepattern are formed on the lower hard mask layer in the first region toexpose portions of the lower hard mask layer. A second pattern includinga second upper hard mask pattern and a second guide pattern is formed.Neutralization patterns are formed on the exposed portions of the lowerhard mask layer in the first region. A block co-polymer layer is formedon the first guide patterns and the neutralization patterns in the firstregion and on the second guide pattern in the second region. The blockco-polymer layer is formed to include first polymer blocks and secondpolymer blocks. The second polymer blocks are removed to expose portionsof the neutralization patterns. The neutralization patterns are etchedusing the first polymer blocks as etch masks to expose portions of thelower hard mask layer in the first region without removing the secondupper hard mask pattern on the lower hard mask layer in the secondregion. The exposed portions of the lower hard mask layer are removed toform first lower hard mask patterns exposing portions of the patternformation layer in the first region.

According to further embodiments, a method of fabricating a fine patternstructure includes forming a pattern formation layer, a lower hard masklayer, an upper hard mask layer and a block co-polymer layer on asubstrate having a first region and a second region. The blockco-polymer layer is formed to include first polymer blocks and secondpolymer blocks which are phase-separated. The first polymer blocks andthe second polymer blocks in the first region are alternately arrayed ina horizontal direction, and the first polymer blocks and the secondpolymer blocks in the second region are randomly arrayed. An etchingprocess is applied to the first region using the first polymer blocks asetch masks. Pattern images of the first and second polymer blocksrandomly arrayed in the second region are not transferred into the lowerhard mask layer in the second region while the patterning process isperformed.

According to further embodiments, a method of fabricating a fine patternstructure includes forming a pattern formation layer over a first regionan a second region of a substrate. A first block co-polymer layer isformed in the first region. A second block co-polymer layer is formed inthe second region. An etching process is applied to the first and secondblock co-polymer layers. The fine pattern structure is formed in thepattern formation layer in the first region without forming a pattern inthe pattern formation layer in the second region.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present disclosure will become more apparent in viewof the attached drawings and accompanying detailed description, inwhich:

FIG. 1 is a plan view illustrating a structure according to anembodiment of the present disclosure;

FIG. 2 is a perspective view including a cross-section taken along lineI-I′ of FIG. 1; and

FIGS. 3 to 22 are schematic views illustrating a method of fabricating afine pattern structure according to an embodiment of the presentdisclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

A plurality of patterns may be uniformly formed in the predeterminedportion of the given region using a block co-polymer (BCP) material.However, undesired random patterns may be non-uniformly formed in aremaining portion of the given region. Thus, additional processes may beperformed to prevent the undesired patterns from being formed in theremaining portion of the given region. For example, an additional photomask may be used to prevent the undesired patterns from being formed inthe remaining portion of the given region.

Embodiments of the present disclosure relate to methods which preventnon-ordered BCP structures from being transferred into an underlyingpattern layer. Further, embodiments relate to methods of fabricatingfine pattern structures. The methods of fabricating the fine patternstructures may be applied to memory devices such as dynamic randomaccess memory (DRAM) devices, static random access memory (SRAM)devices, flash memory devices, magnetic random access memory (MRAM)devices, phase changeable random access memory (PcRAM) devices,resistive random access memory (ReRAM) devices and ferroelectric randomaccess memory (FeRAM) devices, and logic devices such as controllers andmicroprocessors. In the following embodiments, it will be understoodthat when an element is referred to as being located “on”, “over”,“above”, “under”, “beneath” or “below” another element, it can bedirectly contact the other element, or at least one intervening elementmay also be present therebetween. Accordingly, the terms such as “on”,“over”, “above”, “under”, “beneath”, “below” and the like which are usedherein are for the purpose of describing particular embodiments only andare not intended to limit the scope of the present disclosure.

Referring to FIG. 1, a fine pattern structure 100 may include a firstregion 110 and a second region 120 which are distinct from each other.Although FIG. 1 illustrates a configuration in which the first region110 is surrounded by the second region 120, this configuration is merelyone example. In other embodiments, the first and second regions 110 and120 may be arranged differently from the configuration shown in FIG. 1.

In some embodiments, the fine pattern structure 100 may include asemiconductor substrate such as a silicon substrate and an insulationlayer or a conductive layer disposed on the semiconductor substrate. Thefirst region 110 may correspond to a region in which BCP patterns aretransferred to a pattern formation layer, and the second region 120 maycorrespond to a non-pattern region in which BCP patterns are nottransferred to a pattern formation layer. In some embodiments, the firstregion 110 may correspond to a cell region of a semiconductor device,and the second region 120 may correspond to a peripheral circuit regionof the semiconductor device.

Referring to FIG. 2, a pattern formation layer 220 is disposed on asubstrate 210. Although not shown in the drawings, another layer may bedisposed between the substrate 210 and the pattern formation layer 220.In some embodiments, the substrate 210 may be a semiconductor substratesuch as a silicon substrate. Alternatively, the substrate 210 may be aninsulation substrate or a glass substrate. In some embodiments, thepattern formation layer 220 may be a conductive layer or an insulationlayer in which final patterns are formed. Alternatively, the patternformation layer 220 may be a hard mask layer that is used as an etchmask layer when an underlying layer is patterned.

In an embodiment, the pattern formation layer 220 may include a carbonlayer. A lower hard mask layer 230 may be disposed on the patternformation layer 220. The lower hard mask layer 230 may be used as anetch mask layer while portions of the pattern formation layer 220 areselectively etched. Thus, the lower hard mask layer 230 may include amaterial having an etch selectivity with respect to the patternformation layer 220. When the pattern formation layer 220 is a carbonlayer, the lower hard mask layer 230 may include a silicon oxynitride(SiON) layer.

Upper hard mask layers 241 and 242 may be disposed on the lower hardmask layer 230. While the upper hard mask layer 241 in the first region110 has a patterned shape, the upper hard mask layer 242 in the secondregion 120 may have a plate shape to cover an entire surface of thelower hard mask layer 230 in the second region 120. Hereinafter, theupper hard mask layers 241 in the first region 110 and the upper hardmask layer 242 in the second region 120 will be referred to as firstupper hard mask patterns 241 and a second upper hard mask pattern 242,respectively. As described with reference to FIG. 1, the first region110 may be a pattern region in which patterns are formed in patternformation layer 220 using a BCP layer, and the second region 120 may bea non-pattern region in which no patterns are formed in patternformation layer 220 regardless of presence of the BCP layer.

The upper hard mask patterns 241 and 242 may be used as an etch masklayer while portions of the lower hard mask layer 230 are selectivelyetched. Thus, the upper hard mask patterns 241 and 242 may include amaterial having an etch selectivity with respect to the lower hard masklayer 230. In an embodiment in which the lower hard mask layer 230 is asilicon oxynitride (SiON) layer, the upper hard mask patterns 241 and242 may include an oxide layer such as an undoped silicate glass (USG)layer.

In the first region 110, the first upper hard mask patterns 241 may beregularly arrayed to have a predetermined pitch. Thus, portions of thelower hard mask layer 230 in the first region 110 may be exposed betweenportions of the first upper hard mask patterns 241. Neutralizationpatterns 260 may be disposed on the exposed portions of the lower hardmask layer 230 in the first region 110. That is, the first upper hardmask patterns 241 and the neutralization patterns 260 may be alternatelyarrayed on the lower hard mask layer 230 in the first region 110.

In an embodiment, a width W2 of each of the neutralization patterns 260may be three times or greater than three times a width W1 of each of thefirst upper hard mask patterns 241. A thickness of the neutralizationpatterns 260 may be less than a thickness of the first upper hard maskpatterns 241. In some embodiments, each of the neutralization patterns260 may include a neutral surface having a surface energy of about 38dyne/cm to about 45 dyne/cm. The neutralization patterns 260 may includean organic material.

The second upper hard mask pattern 242 may cover an entire surface ofthe lower hard mask layer 230 in the second region 120. Since the secondregion 120 is a non-pattern region, no pattern images are transferredinto the second upper hard mask pattern 242 in the second region 120while the first upper hard mask patterns 241 in the first region 110 areformed. Thus, in an embodiment, the second upper hard mask pattern 242in the second region 120 have a thickness sufficient to prevent patternimages from being transferred into the lower hard mask layer 230 in thesecond region 120 when first polymer blocks constituting a BCP layer inthe first region 110, exposed portions of the neutralization patterns260, and exposed portions of the lower hard mask layer 230 are removed.

Guide layers 251 may be disposed on the first upper hard mask patterns241 in the first region 110, and a guide layer 252 may be disposed onthe second upper hard mask pattern 242 in the second region 120. Whilethe guide layers 251 in the first region 110 has a patterned shape, theguide layer 252 in the second region 120 may have a plate shape coveringan entire surface of the second upper hard mask pattern 242 in thesecond region 120. Hereinafter, the guide layers 251 in the first region110 and the guide layer 252 in the second region 120 will be referred toas guide patterns 251 and a guide pattern 252, respectively. The firstregion 110 may include a plurality of guide patterns 251 and the secondregion 120 may include a single guide pattern 252.

In an embodiment, the guide patterns 251 in the first region 110 may bevertically aligned with the first upper hard mask patterns 241. That is,sidewalls of the guide patterns 251 may be vertically aligned, orcontiguous, with sidewalls of the first upper hard mask patterns 241.Each of the guide patterns 251 and the guide pattern 252 may include thesame material as one of the polymer blocks of the block co-polymer in aBCP layer 270.

A BCP layer 270 may be disposed on the guide patterns 251 and theneutralization patterns 260 in the first region 110, and a BCP layer 280may be disposed on the guide pattern 252 in the second region 120.Herein, the BCP layer 270 disposed in the first region 110 may bereferred to as a first BCP layer 270 and the BCP layer 280 disposed inthe second region 120 may be referred to as a second BCP layer 280. Thefirst and second BCP layers 270 and 280 may be formed in a singleprocess step.

The first BCP layer 270 in the first region 110 may include firstpolymer blocks 271 and second polymer blocks 272. The first polymerblocks 271 and the second polymer blocks 272 may be alternately arrayed.For example, some of the first polymer blocks 271 may be disposed on theguide patterns 251, and the remaining first polymer blocks 271 and thesecond polymer blocks 272 may be alternately arrayed on theneutralization patterns 260 in a horizontal direction as seen in FIG. 2.

In such an embodiment, each of the second polymer blocks 272 may bedisposed adjacent to one of the first polymer blocks 271 disposed on theguide patterns 251. In an embodiment in which the width W2 of eachneutralization pattern 260 is about three times the width W1 of each ofthe first upper hard mask patterns 241, three polymer blocks (e.g., oneof the first polymer blocks 271 and two of the second polymer blocks272) may be laterally arrayed on each neutralization pattern 260.Alternatively, in an embodiment in which the width W2 of eachneutralization pattern 260 is over three times the width W1 of each ofthe first upper hard mask patterns 241, four or more polymer blocks maybe laterally arrayed on each neutralization pattern 260.

The second BCP layer 280 in the second region 120 may include at leastone first polymer block 281 and at least one second polymer block 282.Since the second region 120 includes the single guide pattern 252, theat least one first polymer block 281 and the at least one second polymerblock 282 may be randomly arrayed on the single guide pattern 252. Thatis, the at least one first polymer block 281 and the at least one secondpolymer blocks 282 may be alternately arrayed in a horizontal directionin a portion of the second region 120, and the at least one firstpolymer block 281 and the at least one second polymer blocks 282 may besequentially stacked in a vertical direction in another portion of thesecond region 120.

In some embodiments, the first BCP layer 270 and the second BCP layer280 may be the same BCP material which is formed in the same processstep. In such an embodiment, the first polymer blocks 271 of the firstBCP layer 270 may be the same material as the first polymer blocks 281of the second BCP layer 280, and the second polymer blocks 272 of thefirst BCP layer 270 may be the same material as the second polymerblocks 282 of the second BCP layer 280. In an embodiment, the first andsecond BCP layers 270 and 280 may be formed of apolystyrene-polymethylmethacrylate (PS-PMMA) co-polymer material. Thus,if the guide patterns 251 and the guide pattern 252 are polystyrene (PS)blocks, the first polymer blocks 271 and 281 may be PS blocks and thesecond polymer blocks 272 and 282 may be PMMA blocks.

In some embodiments, the first and second BCP layers 270 and 280 may beformed of polybutadiene-polybutylmethacrylate co-polymer,polybutadiene-polydimethylsiloxane co-polymer,polybutadiene-polymethylmethacrylate co-polymer,polybutadienepolyvinylpyridine co-polymer,polybutylacrylate-polymethylmethacrylate co-polymer,polybutylacrylate-polyvinylpyridine co-polymer,polyisoprene-polyvinylpyridine co-polymer,polyisoprene-polymethylmethacrylate co-polymer,polyhexylacrylatepolyvinylpyridine co-polymer,polyisobutylene-polybutylmethacrylate co-polymer,polyisobutylene-polymethylmethacrylate co-polymer,polyisobutylene-polybutylmethacrylate co-polymer,polyisobutylene-polydimethylsiloxane co-polymer,polybutylmethacrylate-polybutylacrylate co-polymer,polyethylene-polymethylmethacrylate co-polymer,polystyrene-polybutylmethacrylate co-polymer, polystyrene-polybutadieneco-polymer, polystyrene-polyisoprene co-polymer,polystyrene-polydimethylsiloxane co-polymer,polystyrene-polyvinylpyridine co-polymer,polyethylethylene-polyvinylpyridine co-polymer,polyethylene-polyvinylpyridine co-polymer,polyvinylpyridine-polymethylmethacrylate co-polymer,polyethyleneoxide-polyisoprene co-polymer,polyethyleneoxide-polybutadiene co-polymer,polyethyleneoxide-polystyrene co-polymer,polyethyleneoxide-polymethylmethacrylate co-polymer,polyethyleneoxide-polydimethylsiloxane co-polymer, orpolystyrene-polyethyleneoxide co-polymer. In other embodiments, thefirst and second BCP layers 270 and 280 may be formed of a tri-blockco-polymer material having three distinct polymer blocks or amulti-block co-polymer material having four or more distinct polymerblocks.

FIGS. 3 to 22 are schematic views illustrating a method of fabricating afine pattern structure according to an embodiment of the presentdisclosure. FIGS. 4, 6, 8, 10, 12, 14, 16, 18, 20 and 22 arecross-sectional views taken along lines II-II′ of FIGS. 3, 5, 7, 9, 11,13, 15, 17, 19 and 21, respectively.

Referring to FIGS. 3 and 4, a lower hard mask layer 230 may be formed ona pattern formation layer 220 disposed on a substrate 210 having a firstregion 110 and a second region 120. The first region 110 may be apattern region in which fine patterns are formed, and the second regionmay be a non-pattern region in which no fine patterns are formed belowBCP layers, and in which no patterns are formed in a pattern formationlayer. In some embodiments, the substrate 210 may be a semiconductorsubstrate such as a silicon substrate or an insulation substrate such asa glass substrate.

The pattern formation layer 220 may be a layer in which final patternsare formed. Alternatively, the pattern formation layer 220 may be a hardmask layer that is used as an etch mask when an underlying layer ispatterned. In such an embodiment, at least one layer may be additionallyformed between the substrate 210 and the pattern formation layer 220.

In some embodiments, the pattern formation layer 220 may include acarbon layer. The lower hard mask layer 230 may be used as an etch maskwhile portions of the pattern formation layer 220 are selectively etchedin a subsequent process. Thus, the lower hard mask layer 230 may beformed of a material having an etch selectivity with respect to thepattern formation layer 220. When the pattern formation layer 220 isformed of a carbon layer, the lower hard mask layer 230 may be formed ofa silicon oxynitride (SiON) layer.

An upper hard mask layer 240 may be formed on the lower hard mask layer230. The upper hard mask layer 240 may be used as an etch mask layerwhile portions of the lower hard mask layer 230 are selectively etchedin a subsequent process. Thus, the upper hard mask layer 240 may beformed to include a material having an etch selectivity with respect tothe lower hard mask layer 230. When the lower hard mask layer 230 isformed of a silicon oxynitride (SiON) layer, the upper hard mask layer240 may be formed to include an oxide layer, for example, an undopedsilicate glass (USG) layer. The upper hard mask layer 240 may be formedto have a sufficient thickness to remain over the entire second region120 while a patterning process is performed in the first region 110.

A guide layer 250 may then be formed on the upper hard mask layer 240.The guide layer 250 may be formed of a material which includes a polymerof a polymer block in a block co-polymer (BCP) layer which is formed ina subsequent process. For example, if the BCP layer is formed of apolystyrene-polymethylmethylacrylate (PS-PMMA) co-polymer material, theguide layer 250 may be formed of polystyrene (PS).

Referring to FIGS. 5 and 6, photoresist patterns 290 may be formed onthe guide layer 250. While the photoresist patterns 290 in the firstregion 110 may expose portions of the guide layer 250, the photoresistpattern 290 in the second region 120 may cover an entire surface of theguide layer 250 located in the second region 120. In some embodiments,the photoresist patterns 290 in the first region 110 may be linepatterns which are regularly arrayed to have a predetermined pitch. Thatis, the photoresist patterns 290 in the first region 110 may be formedto have a line and space form.

A width W2 of spaces between the photoresist patterns 290 in the firstregion 110 may be at least three times a width W1 of each photoresistpattern 290 in the first region 110. In an embodiment, the width W1 maybe controlled to be substantially the same as a width of fine patternswhich are formed in or below pattern formation layer 220. Thus, atrimming process may be applied to the photoresist patterns 290 tocontrol the width W1 of the photoresist patterns 290 in the first region110.

Referring to FIGS. 7 and 8, the guide layer 250 and the upper hard masklayer 240 may be etched using the photoresist patterns 290 as etchmasks. After etching the guide layer 250 and the upper hard mask layer240, all of the photoresist patterns 290 may be removed. As a result,first upper hard mask patterns 241 and guide patterns 251 may be formedin the first region 110 to expose portions of the lower hard mask layer230, and second upper hard mask pattern 242 and guide pattern 252 may beformed in the second region 120 to cover an entire surface of the lowerhard mask layer 230.

Each of the first upper hard mask patterns 241 and the guide patterns251 in the first region 110 may have a width which is substantially thesame as the width W1 of each photoresist pattern 290 formed in the firstregion 110. In addition, a width of each of the exposed portions of thelower hard mask layer 230 may be substantially the same as the width W2of each of the spaces between the photoresist patterns 290 in the firstregion 110. Thus, the width W2 of each of the exposed portions of thelower hard mask layer 230 may also be at least three times the width W1of each of the first upper hard mask patterns 241 and the guide patterns251.

Referring to FIGS. 9 and 10, a neutralization layer may be formed on atop surface of the substrate in at least the first region 110, and theneutralization layer may be recessed to expose the guide patterns 251and 252 and to form neutralization patterns 260 on the exposed portionsof the lower hard mask layer 230. The neutralization layer may berecessed such that a thickness of the neutralization patterns 260 isless than a thickness of the first upper hard mask patterns 241. Theneutralization patterns 260 may be formed without removing portions ofthe guide pattern 252 in the second region 120.

In some embodiments, the neutralization patterns 260 may be formed of anorganic material. Each of the neutralization patterns 260 may be formedto include a neutral surface having a surface energy of about 38 dyne/cmto about 45 dyne/cm. Because the neutralization patterns 260 are formedto have neutral surfaces, a plurality of polymer blocks of a BCP layerformed in a subsequent process may be phase-separated and verticallyaligned on the neutralization patterns 260.

Referring to FIGS. 11 and 12, a BCP layer 300 may be formed on the guidepatterns 251, the neutralization patterns 260 and the guide pattern 252.The BCP layer 300 may be formed using a spin coating process. In someembodiments, the BCP layer 300 may include first polymer blocks andsecond polymer blocks which are combined with each other by covalentbonds. In such an embodiment, a volume ratio of the first polymer blocksand second polymer blocks may be about 1:1. In an embodiment, the BCPlayer 300 may be formed of a polystyrene-polymethylmethylacrylate(PS-PMMA) co-polymer material including polystyrene (PS) blocks(corresponding to the first polymer blocks) covalently bonded topolymethylmethylacrylate (PMMA) blocks (corresponding to the secondpolymer blocks).

However, the PS-PMMA co-polymer material is merely an example of asuitable material for the BCP layer 300. In some embodiments, the BCPlayer 300 may be formed of polybutadiene-polybutylmethacrylateco-polymer, polybutadiene-polydimethylsiloxane co-polymer,polybutadiene-polymethylmethacrylate co-polymer,polybutadiene-polyvinylpyridine co-polymer,polybutylacrylate-polymethylmethacrylate co-polymer,polybutylacrylate-polyvinylpyridine co-polymer,polyisoprene-polyvinylpyridine co-polymer,polyisoprene-polymethylmethacrylate co-polymer,polyhexylacrylate-polyvinyl pyridine co-polymer,polyisobutylene-polybutylmethacrylate co-polymer,polyisobutylene-polymethylmethacrylate co-polymer,polyisobutylene-polybutylmethacrylate co-polymer,polyisobutylene-polydimethylsiloxane co-polymer,polybutylmethacrylate-polybutylacrylate co-polymer,polyethylethylene-polymethylmethacrylate co-polymer,polystyrene-polybutylmethacrylate co-polymer, polystyrene-polybutadieneco-polymer, polystyrene-polyisoprene co-polymer,polystyrene-polydimethylsiloxane co-polymer,polystyrene-polyvinylpyridine co-polymer,polyethylethylene-polyvinylpyridine co-polymer,polyethylene-polyvinylpyridine co-polymer,polyvinylpyridine-polymethylmethacrylate co-polymer,polyethyleneoxide-polyisoprene co-polymer,polyethyleneoxide-polybutadiene co-polymer,polyethyleneoxide-polystyrene co-polymer,polyethyleneoxide-polymethylmethacrylate co-polymer,polyethyleneoxide-polydimethylsiloxane co-polymer, orpolystyrene-polyethyleneoxide co-polymer. Alternatively, the BCP layer300 may be formed of a tri-block co-polymer material having threedistinct polymer blocks or a multi-block co-polymer material having fouror more distinct polymer blocks.

Referring to FIGS. 13 and 14, the BCP layer 300 may be annealed to bephase-separated into first polymer blocks 271 and second polymer blocks272. For example, if the BCP layer 300 is formed of a PS-PMMA co-polymermaterial, the BCP layer 300 may be phase-separated into PS blocks(corresponding to the first polymer blocks 271) and PMMA blocks(corresponding to the second polymer blocks 272) by an annealingprocess. In the first region 110, the first polymer blocks 271 composedof the PS blocks may be disposed on the guide patterns 251 andvertically aligned with the guide patterns 251. If the guide patterns251 are formed to have line shapes, the first polymer blocks 271 mayalso be formed to have line shapes, as illustrated in FIG. 13.

The first polymer blocks 271 and the second polymer blocks 272 may bealternately arrayed on each of the neutralization patterns 260. In suchan embodiment, the second polymer blocks 272 may be formed on edges ofthe neutralization patterns 260 to contact the first polymer blocks 271disposed on the guide patterns 251. As such, the first polymer blocks271 and the second polymer blocks 272 having line shapes may bealternately arrayed on each of the neutralization patterns 260. Athickness of the first polymer blocks 271 on the neutralization patterns260 may be substantially the same as a thickness of the second polymerblocks 272 on the neutralization patterns 260. In contrast, a thicknessof the first polymer blocks 271 on the neutralization patterns 260 maybe greater than a thickness of the first polymer blocks 271 on the guidepatterns 251. This is due to a level difference between top surfaces ofthe neutralization patterns 260 and top surfaces of the guide patterns251 when top surfaces of first polymer blocks 271 are level with topsurfaces of second polymer blocks 272.

The first polymer blocks 271 and the second polymer blocks 272 may bealternately arrayed in a horizontal direction on a portion (of the guidepattern 252 in the second region 120 (region “B”), and may be verticallystacked on another portion of the guide pattern 252 in the second region120 (region “A”), as illustrated in FIGS. 13 and 14. The variousarrangements may occur when the guide pattern 252 is a single extendsacross an entire portion of the second region 120. Thus, the firstpolymer blocks 271 and the second polymer blocks 272 may be randomlyarrayed in the second region 120.

Pattern images of the first polymer blocks 271 and the second polymerblocks 272 randomly arrayed in the second region 120 are not transferredinto the underlying pattern formation layer 230 when the patternformation layer 230 in the first region 110 is patterned in a subsequentprocess. In region “B”, a thickness of the first polymer blocks 271 maybe substantially the same as a thickness of the second polymer blocks272. In addition, the thickness of the first and second polymer blocks271 and 272 formed in region “B” may be substantially the same as athickness of the first polymer blocks 271 formed on the guide patterns251 in first region 110.

Referring to FIGS. 15 and 16, the second polymer blocks 272 may beselectively removed. The first polymer blocks 271 (e.g., PS blocks) mayhave a solubility which is different from a solubility of the secondpolymer blocks 272 (e.g., PMMA blocks). Thus, the second polymer blocks272 may be selectively removed using a wet etch process that employs aspecific solution, which is capable of selectively dissolving only thesecond polymer blocks 272, as an etchant. Selective removing the secondpolymer blocks 272 may expose portions of the neutralization patterns260 in the first region 110.

While the second polymer blocks 272 are selectively removed, the secondpolymer block 272 stacked on the first polymer block 271 in region “A”may also be removed to expose the underlying first polymer block 271. Insuch an embodiment, the underlying first polymer block 271 may also beetched to reduce a thickness of the first polymer block 271. While thesecond polymer blocks 272 are selectively removed, the second polymerblocks 272 laterally arrayed in region “B” may also be removed to exposeportions of the underlying guide pattern 252 in the second region 120.In such an embodiment, the underlying guide pattern 252 may also beetched to reduce a thickness of the guide pattern 252 when a thicknessof the second polymer block 272 in region “B” is less than a thicknessof the second polymer blocks 272 in the first region 110.

Referring to FIGS. 17 and 18, the exposed portions of the neutralizationpatterns 260 may be etched using the first polymer blocks 271 as etchmasks to expose portions of the lower hard mask layer 230 in the firstregion 110. Subsequently, the exposed portions of the lower hard masklayer 230 in the first region 110 may be etched by a predeterminedthickness. While the neutralization patterns 260 and the lower hard masklayer 230 in the first region 110 are etched using the first polymerblocks 271 as etch masks, portions of first polymer blocks 271 on theguide patterns 251 may be completely removed to expose the guidepatterns 251 in the first region 110. In the meantime, while theneutralization patterns 260 and the lower hard mask layer 230 in thefirst region 110 are etched using the first polymer blocks 271 as etchmasks, the first polymer blocks 271 on the neutralization patterns 260may be partially etched. Thus, top surfaces of the first polymer blocks271 remaining on the neutralization patterns 260 may be substantiallycoplanar with top surfaces of the guide patterns 251.

In an embodiment, the first polymer blocks 271 and the guide pattern 252in region “A” of the second region 120 may be completely removed toexpose a portion of the second upper hard mask pattern 242 and theexposed portion of the second upper hard mask pattern 242 may also bepartially etched by a predetermined thickness. The first polymer blocks271 in region “B” of the second region 120 may be completely removed toexpose a top surface of the guide pattern 252.

The exposed guide pattern 252 in region “B” of the second region 120 maybe removed to expose a portion of the second upper hard mask pattern242, and the exposed portion of the second upper hard mask pattern 242may also be etched by a predetermined thickness. Thus, a thickness ofthe etched portion of second upper hard mask pattern 242 remaining inthe region “B” may be less than a thickness of the portion of secondupper hard mask pattern 242 remaining in region “A”.

Referring to FIGS. 19 and 20, the exposed portions of the lower hardmask layer 230 in the first region 110 may be continuously etched untilthe pattern formation layer 220 is exposed. As a result, arrayed firstlower hard mask patterns 231 may be formed in the first region 110, anda second lower hard mask pattern 232 may be formed over an entiresurface the second region 120. When the first lower hard mask patterns231 are formed, the guide patterns 251 and the first polymer blocks 271remaining in the first region 110 may be completely removed and apredetermined thickness of the first upper hard mask patterns 241 mayremain. Accordingly, line-shaped structures 401 and line-shapedstructures 402 may be alternately arrayed on the pattern formation layer220 in the first region 110. Each line-shaped structure 401 may includefirst lower hard mask pattern 231 and first upper hard mask pattern 241which are sequentially stacked, and each of the line-shaped structures402 may consist of the first lower hard mask pattern 231.

An etch rate of the second upper hard mask pattern 242 may be lower thanan etch rate of the second lower hard mask pattern 232. Accordingly, thesecond upper hard mask pattern 242 may still remain in second region 120even after the first lower hard mask patterns 231 are formed. Athickness of the second upper hard mask pattern 242 remaining in region“A” of the second region 120 may be substantially the same as athickness of the first upper hard mask patterns 241 remaining in thefirst region 110.

In an embodiment, an etch rate of the second upper hard mask pattern 242may be lower than an etch rate of the second lower hard mask pattern232. Thus, a remaining portion of the second upper hard mask pattern 242located under the guide pattern 252 (see FIG. 18) in region “B” mayremain to have a thickness which is greater than a thickness of thesecond upper hard mask pattern 242 remaining in region “A”.

A portion of the second upper hard mask pattern 242 that was previouslylocated under the second polymer block 272 (see FIG. 14) in region “B”may be removed to expose the second lower hard mask pattern 232. In suchan embodiment, patterns are not formed in the second lower hard maskpattern 232 in the second region 120 when the first lower hard maskpatterns 231 are formed in the first region 110.

Referring to FIGS. 21 and 22, the pattern formation layer 220 may beetched in region “A” using line-shaped structures 401 and 402 of FIG. 20and the second lower hard mask pattern 232 as etch masks until anunderlying layer, for example, substrate 210 is exposed. As a result,final patterns 221 defining openings that expose portions of thesubstrate 210 may be formed in the first region 110, and a contiguousdummy layer 222 may be formed over an entire upper surface of the secondregion 120.

When an etch process is performed to form the final patterns 221 and thedummy layer 222, the first upper hard mask patterns 241 remaining in thefirst region 110 may be completely removed and the first lower hard maskpatterns 231 may still remain. In an embodiment, the second upper hardmask pattern 242 may be completely removed and a predetermined thicknessof the second lower hard mask pattern 232 may remain. A thickness of thesecond lower hard mask pattern 232 remaining in region “A” of the secondregion 120 may be substantially the same as a thickness of the firstlower hard mask patterns 231 remaining in the first region 110.

Meanwhile, a portion of the second upper hard mask pattern 242 that waspreviously located under the guide pattern 252 (see FIG. 18) in region“B” may be completely removed and a predetermined thickness of a portionof the second lower hard mask pattern 232 in region “B” may remain. Aportion of the second lower hard mask pattern 232 remaining in region“B” may be thicker than a portion of the second lower hard mask pattern232 remaining in region “A”.

In addition, a portion of the second lower hard mask pattern 232 thatwas previously located under the second polymer block 272 (see FIG. 14)in region “B” may be removed to expose the dummy layer 222. In anembodiment, the dummy layer 222 in the second region 120 is notpatterned when the final patterns 221 are formed in the first region110. With reference to FIGS. 13 and 14, patterns corresponding to thefirst and second polymer blocks 271 and 272 disposed in the secondregion 120 are not transferred into the pattern formation layer 220.After the final patterns 221 are formed in the first region 110, thefirst lower hard mask patterns 231 and 232 remaining in the first andsecond regions 110 and 120 may be removed.

In an embodiment, pattern images generated by two or more distinctpolymer blocks randomly disposed in a second region are not transferredinto an underlying pattern formation layer disposed in a non-patternregion while fine patterns are formed in a pattern region of the patternformation layer using a BCP layer. Fine pattern structures andfabrication methods may be used in polarizing plates or in reflectivelenses of reflective liquid crystal display (LCD) units. The finepattern structures which may be nano structures may be used inpolarizing plates as well as other polarizing parts including displaypanels. For example, nano structures according to embodiments of thisdisclosure may be used in fabrication array substrates including thinfilm transistors or in processes for directly forming the polarizingparts on color filter substrates. Further, embodiments of nanostructures may be used in molding processes for fabricating nanowiretransistors or memories, electronic components for patterningnano-scaled interconnections, catalysts of solar cells and fuel cells,etch masks, organic light emitting diodes (OLEDs), and gas sensors.

Methods according to the aforementioned embodiments and structuresformed thereby may be used in fabrication of integrated circuit (IC)chips. The IC chips may be supplied to users in a raw wafer form, in abare die form or in a package form. The IC chips may be supplied in asingle package form or in a multi-chip package form. The IC chips may beintegrated in intermediate products such as mother boards or endproducts to constitute signal processing devices. The end products mayinclude toys, low end application products, or high end applicationproducts such as computers. For example, the end products may includedisplay units, keyboards, or central processing units (CPUs).

While embodiments of the present disclosure have been particularly shownand described with reference to specific examples, it will be understoodthat various changes in form and details may be made therein withoutdeparting from the spirit and scope of the following claims.

What is claimed is:
 1. A method of fabricating a fine pattern structure,the method comprising: forming a pattern formation layer and a lowerhard mask layer on a substrate having a first region and a secondregion; forming a first pattern including first upper hard mask patternand a first guide pattern on the lower hard mask layer in the firstregion to expose portions of the lower hard mask layer; forming a secondpattern including a second upper hard mask pattern and a second guidepattern; forming neutralization patterns on the exposed portions of thelower hard mask layer in the first region; forming a block co-polymerlayer on the first guide patterns and the neutralization patterns in thefirst region and on the second guide pattern in the second region, theblock co-polymer layer including first polymer blocks and second polymerblocks; removing the second polymer blocks to expose portions of theneutralization patterns; etching the neutralization patterns using thefirst polymer blocks as etch masks to expose portions of the lower hardmask layer in the first region without removing the second upper hardmask pattern on the lower hard mask layer in the second region; andremoving the exposed portions of the lower hard mask layer to form firstlower hard mask patterns exposing portions of the pattern formationlayer in the first region.
 2. The method of claim 1, wherein the firstregion is a region in which the pattern formation layer is etched andthe second region is a region in which the pattern formation layer isnot etched.
 3. The method of claim 1, wherein forming the first patternand the second pattern includes: sequentially forming an upper hard masklayer and a guide layer on the lower hard mask layer; forming aphotoresist pattern on the guide layer, the photoresist pattern exposingportions of the guide layer in the first region and covering an entiresurface of the guide layer in the second region; removing the exposedportions of the guide layer to form first guide patterns in the firstregion; removing portions of the upper hard mask layer exposed by thefirst guide patterns to form first upper hard mask patterns in the firstregion; and removing the photoresist pattern.
 4. The method of claim 1,wherein the guide layer is formed of the same material as the firstpolymer block or the second polymer block.
 5. The method of claim 1,wherein forming the neutralization patterns includes: forming aneutralization layer on an entire surface of the substrate including thefirst and second patterns; and recessing the neutralization layer toexpose the first and second guide patterns and to leave portions of theneutralization layer on the exposed portions of the lower hard masklayer.
 6. The method of claim 1, wherein a thickness of theneutralization patterns is less than a thickness of the first upper hardmask patterns.
 7. The method of claim 1, wherein a width of each of theexposed portions of the lower hard mask layer in the first region isthree times or greater than a width of each of the first upper hard maskpatterns.
 8. The method of claim 1, wherein the block co-polymer layeris formed such that the first polymer blocks and the second polymerblocks in the first region are alternately arrayed in a horizontaldirection and the first polymer blocks and the second polymer blocks inthe second region are randomly arrayed.
 9. The method of claim 1,further comprising etching a portion of the pattern formation layer inthe first region using the first lower hard mask patterns as etch masksto form final patterns in the first region.
 10. A method of fabricatinga fine pattern structure, the method comprising: forming a patternformation layer, a lower hard mask layer, an upper hard mask layer and ablock co-polymer layer on a substrate having a first region and a secondregion, the block co-polymer layer being formed to include first polymerblocks and second polymer blocks which are phase-separated, the firstpolymer blocks and the second polymer blocks in the first region beingalternately arrayed in a horizontal direction, and the first polymerblocks and the second polymer blocks in the second region being randomlyarrayed; and etching the first region using the first polymer blocks asetch masks, wherein pattern images of the first and second polymerblocks randomly arrayed in the second region are not transferred intothe lower hard mask layer in the second region while the patterningprocess is performed.
 11. A method of fabricating a fine patternstructure, the method comprising: forming a pattern formation layer overa first region and a second region of a substrate; forming a first blockco-polymer layer in the first region; forming a second block co-polymerlayer in the second region; etching the first and second blockco-polymer layers; and forming the fine pattern structure in the patternformation layer in the first region without forming a pattern in thepattern formation layer in the second region.
 12. The method of claim11, further comprising: forming horizontally arrayed mask patterns overthe pattern formation layer in the first region; and formingneutralization patterns between the mask patterns, wherein the firstblock co-polymer layer is formed over the mask patterns and over theneutralization patterns.
 13. The method of claim 12, wherein the firstblock co-polymer layer and the second block co-polymer layer eachcomprise first polymer blocks and second polymer blocks that are adifferent polymer from the first polymer blocks.
 14. The method of claim13, wherein the first polymer blocks are alternately arrayed with thesecond polymer blocks in the first region.
 15. The method of claim 13,wherein forming the first block co-polymer layer includes: forming atleast two first polymer blocks arrayed over the neutralization patterns,forming at least one second polymer block between the two first polymerblocks; and forming a second polymer block over the mask patterns. 17.The method of claim 16, wherein a width of the mask patterns is at leastthree times greater than a width of the neutralization patterns.
 18. Themethod of claim 16, further comprising: removing the second polymerblocks to form spaces between the first polymer blocks in the firstregion; and etching the spaces between the first polymer blocks toremove portions of the neutralization layer.
 19. The method of claim 18,further comprising: forming a lower hard mask layer over the patternformation layer; and etching the lower hard mask layer using the maskpatterns as an etch mask.
 20. The method of claim 12, wherein formingthe horizontally arrayed mask patterns comprises: forming a lower hardmask layer over the pattern formation layer; forming an upper hard masklayer over the lower hard mask layer; forming a photoresist patterncovering an entire upper surface of the second region and portions of anupper surface of the first region; and etching the portions of the uppersurface of the first region to remove portions of the hard mask layerand portions of the upper hard mask layer in the first region using thephotoresist pattern as an etch mask.